Abstract
When animated by appreciable temperature gradients, the tendency of gases to slip over non-isothermal solid surfaces is governed by inherently nonlinear equations. Using a simple two-dimensional channel configuration, wherein gas motion is driven by an externally imposed spatially periodic temperature input, it is demonstrated that this nonlinearity results in thermal rectification: periodic temperature inputs that break left-right symmetry can generate a net mass flux along the channel. This flux is not predicted by the commonly employed small-temperature-difference linearized model.